Industrial FLX Premix Watertube Boiler — Steam and Hot Water

CB Boiler Model FLX Premix

CB Model FLX Premix

Cleaver-Brooks FLX PremixThe Model FLXPM Flextube boiler achieves best-in-class combustion performance with low emissions. Premix burner technology enables the boiler to attain <20 ppm NOx without FGR and <10 CO as standard on natural gas. The modulating burner control automatically adjusts the air/gas mixture for maximum efficiency and optimum 5:1 turndown.

  • Steam and hot water
  • 75 to 250 HP
  • Available to <9 ppm NOx, ultra-low CO
  • Natural gas or propane fuel
  • Premix burner technology

Product Overview

The FLXPM integrates a servo-driven, fuel-input control valve with air-input control via a variable-frequency-driven fan for precise fuel/air ratio control.

Its compact design makes it easy to fit several units into a boiler room or into a larger hydronic system of condensing or non-condensing boilers. This multi-unit solution helps to divide the load more efficiently in a hydronic or in a steam process.

Because there is no requirement for FGR piping from the stack to the burner, it is easy to incorporate the FLXPM into a new or existing boiler system.


  • Small footprint
  • Ultra quiet
  • Design protects against thermal stresses
  • Hinged burner door for easy access
  • 25-year warranty


  • Lower Fuel Cost
  • Lower Emissions


  • Process Steam
  • Industrial Process
  • Building Heat
  • Sterilization
  • Hospital and Healthcare